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81.
研究了瓦氏马尾藻(Sargassum vachellianum)规模化育苗及海区养殖技术。采集海区成熟藻体, 室内催熟放散受精卵, 收集并喷洒于水泥板、棕绳、木板3种附着基, 进行受精卵附着、萌发及苗体生长等实验, 发现棕绳育苗效果最佳。受精卵喷洒10d后, 3种附着基的出苗率分别为 85.5%、80.2%和91.3%, 平均株高约1.3 mm。前20天木板幼苗密度最高, 达8.2株/cm2, 但幼苗均生长缓慢。第30天, 幼苗出现明显分枝, 生长率增大到前20天的1.6倍, 其中棕绳幼苗株高最大, 幼苗存活率分别为83.6%、79.7%和75.6%。第60天棕绳幼苗密度及平均株高均最大。将附有幼苗的水泥板(藻礁)、棕绳放入海区进行养殖, 发现幼苗在浪大流急海区生长较快, 4周后平均株高分别达98.7和103.1 mm, 是对照组的1.5倍, 但棕绳脱苗严重。藻礁较适合海区规模化投放养殖, 是藻场修复和重建的理想材料。 相似文献
82.
当今的城市化进程面临诸多问题,在生态文明的时代背景下,城市替代了乡村成为国人的主要人居环境。生态文明旨在倡导重构人与自然的关系。那么,荒野景观作为最本真的生态自然,理应成为人们市居生活的重要体验对象与审美对象。荒野哲学以其对人类生存家园损毁的忧患意识以及对当下生产生活方式的深刻反思逐渐成为哲学思考的重要组成部分。在当今城市中,荒野的价值应该得以重估,荒野景观应当得以复魅。城市对荒野的呼唤、城市审美对荒野的悦纳,是当今中国城乡可持续建设的重大使命。在生态文明的当今社会,人们在市居生活中需要倡导一种审美观念,即荒野审美。荒野审美观的构建正逐渐趋向成熟。 相似文献
83.
Mental health crucially depends upon affective states such as emotions, stress responses, impulses and moods. These states shape how we think, feel and behave. Often, they support adaptive functioning. At other times, however, they can become detrimental to mental health via maladaptive affect generation processes and/or maladaptive affect regulation processes. Here, we present an integrative framework for considering the role of affect generation and regulation in mental illness and well‐being. Our model views affect generation as an iterative cycle of attending to, appraising and responding to situations. It views affect regulation as an iterative series of decisions aimed at altering affect generation. Affect regulation decisions include identifying what, if anything, should be changed about affect, selecting where to intervene in the affect generation cycle, choosing how to implement this intervention, and monitoring the regulation attempt to decide whether to maintain, switch or stop it. Difficulties with these decisions, often arising from biased inputs to them, can contribute to manifestations of mental illness such as clinical symptoms, syndromes and disorders. The model has a number of implications for clinical assessment and treatment. Specifically, it offers a common set of concepts for characterizing different affective states; it highlights interactions between affect generation and affect regulation; it identifies assessment and treatment targets among the component processes of affect regulation; and it is applicable to prevention and treatment of mental illness as well as to promotion and restoration of psychological well‐being. 相似文献
84.
Aims
The nutrient uptake, requirement and releasing rates of bryophytes are very different from those of tracheophytes. However, it is difficult to make a quantitative evaluation of bryophytes’ roles in nutrient cycling and their specific eco-physiological adaptations due to lack of knowledge of their concentrations and stoichiometric ratios of carbon (C), nitrogen (N) and phosphorus (P). To fill this gap, the present study aims to investigate: (i) what are the elevational trends of C, N and P concentrations and stoichiometric ratios of bryophytes? (ii) whether C, N and P concentrations and stoichiometric ratios of bryophytes differ between different bryophyte types (in terms of the growth form and living substrate)? and (iii) how do the exponent scalings of N and P of bryophytes change along the elevational gradient? 相似文献
85.
86.
Shih‐Fan Chan Wei‐Kai Shih An‐Yu Chang Sheng‐Feng Shen I‐Ching Chen 《Ecology letters》2019,22(10):1668-1679
How abiotic and biotic factors constrain distribution limits at the harsh and benign edges of species ranges is hotly debated, partly because macroecological experiments testing the proximate causes of distribution limits are scarce. It has long been recognized – at least since Darwin’s On the Origin of Species – that a harsh climate strengthens competition and thus sets species range limits. Using thorough field manipulations along a large elevation gradient, we show the mechanisms by which temperature determines competition type, resulting in a transition from interference to exploitative competition from the lower to the upper elevation limits in burying beetles (Nicrophorus nepalensis). This transition is an example of Darwin’s classic hypothesis that benign climates favor direct competition for highly accessible resources while harsh climates result in competition through resources of high rivalry. We propose that identifying the properties of these key resources will provide a more predictive framework to understand the interplay between biotic and abiotic factors in determining geographic range limits. 相似文献
87.
粘合材料作为一种重要的辅助材料,在工业包装、海洋工程以及生物医药等多个领域都有广泛的应用需求。天然存在的粘合剂如贻贝足丝粘合蛋白等具有良好的生物相容性和生物可降解性,但因其来源受限及在生理环境下较弱的粘合性能,因此在生物医药领域的应用受到了限制。从自然生物的粘合现象中汲取灵感,各种利用化学或生物合成方法制备的仿生粘合材料应运而生,针对生物医药领域的特定需求,一些新兴粘合材料在生物相容性、生物可降解性以及组织粘附等方面都表现出在医药领域应用的潜力。展望未来,受自然粘合材料兼具环境响应、自我再生和自修复等特征的启迪,各种生物灵感和生物仿生粘合材料的开发势必是未来的发展热点,而合成生物学技术为创建具有上述特征的活体粘合材料提供了新的可能。 相似文献
88.
Mating behavior of the Hog-badger (Arctonyx collaris) was recorded on 463 videos (totally 8053 s) taken with auto-trigger cameras between March 13 and May 13, 2017 in Jiangxi Wuyishan. Males followed and guarded the females for several hours before mating. One mounting behavior, and three mating behaviors were observed from 01:55 to 08:49 on April 18. The durations of mating behaviors lasted for 731s, 1690s and 1494s, respectively. Based on these observations, we found: 1) mating behavior was controlled by the female, including obvious sexual solicitations; 2) females can mate more than one time within one estrous cycle; 3) quickly and repeatedly pumping and inserting behavior was observed in male during mating. 相似文献
89.
90.
Wenhua Su Mengyan Du Fangrui Lin Chenshuang Zhang Tongsheng Chen 《Journal of biophotonics》2019,12(4)
The spontaneous excitation‐emission (ExEm) spectrum is introduced to the quantitative mExEm‐spFRET methodology we recently developed as a spectral unmixing component for quantitative fluorescence resonance energy transfer measurement, named as SPEES‐FRET method. The spectral fingerprints of both donor and acceptor were measured in HepG2 cells with low autofluorescence separately expressing donor and acceptor, and the spontaneous spectral fingerprint of HEK293 cells with strong autofluoresence was measured from blank cells. SPEES‐FRET was performed on improved spectrometer‐microscope system to measure the FRET efficiency (E) and concentration ratio (R C) of acceptor to donor vales of FRET tandem plasmids in HEK293 cells, and obtained stable and consistent results with the expected values. Moreover, SPEES‐FRET always obtained stable results for the bright and dim cells coexpressing Cerulean and Venus or Cyan Fluorescent Protein (CFP)‐Bax and Yellow fluorescent protein (YFP)‐Bax, and the E values between CFP‐Bax and YFP‐Bax were 0.02 for healthy cells and 0.14 for the staurosporine (STS)‐treated apoptotic cells. Collectively, SPEES‐FRET has very strong robustness against cellular autofluorescence, and thus is applicable to quantitative evaluation on the protein‐protein interaction in living cells with strong autofluoresence. 相似文献